Answer:
C.0 
since it's literally impossible for a triangle to have a right angle only squares and other shapes. triangles are made of acute angles
 
        
             
        
        
        
Equation: 7x - 3y = 21
3y = 7x - 21
Divide both sides by 3, 
y = 7/3x - 7
Compare it with principle equation, y = mx + c
Here, slope (m) = 7/3
In short, Your Answer would be: 7/3
Hope this helps!
        
             
        
        
        
Answer:  y=7,x=3
Steps:
y = 2x + 1
3x + y = 16
Substitute y = 2x + 1
3x + 2x + 1 = 16
Simplify
5x+1=16
Isolate x for 5x + 1 = 16: x = 3
For y = 2x + 1
Substitute x = 3
y = 2 · 3 + 1
Simplify
y = 7
The solutions to the system of equations are:
y = 7, x = 3
Hope This Helps!
 
        
             
        
        
        
Green or purple = 10
prob(green or purple) = 10/30 = 1/3